Caltrans says OK to Agoura wildlife bridge

OVER THE TOP—A rendering shows the wildlife corridor spanning both the freeway and Agoura Road. Courtesy of Resource Conservation District of the Santa Monica Mountains

OVER THE TOP—A rendering shows the wildlife corridor spanning both the freeway and Agoura Road. Courtesy of Resource Conservation District of the Santa Monica Mountains

The California Department of Transportation gave approval Tuesday for a plan to build a $60-million wildlife freeway crossing in Agoura Hills.

The unpaved bridge across the 101 Freeway at Liberty Canyon will feature a natural landscape design to encourage mountain lions, bobcats and other wildlife to safely cross the highway and expand their habitat from the Simi Hills in the north to the Santa Monica Mountains and the Pacific Ocean in the south.

Caltrans expects the design phase to be completed in two years, followed by construction possibly starting in late 2020, depending on funding availability.

The agency announced May 1 that no public funds would be used in the project, but issued a revised statement the following day acknowledging that a combinaton of private donations and taxpayers dollars would be needed to meet the full cost.

“The estimated cost of $60 million is expected to be funded through a mix of private philanthropy, corporate donations and public conservation grants,” Caltrans said.

The private fundraising will be led by the National Wildlife Federation. The group hopes to collect $10 million in starter money by the end of 2018.

“Caltrans is excited to be working with the National Wildlife Federation, National Park Service, Santa Monica Mountains Conservancy and our other valued partners in this important effort toward developing a sustainable wildlife crossing,” Caltrans District 7 Director Carrie Bowen said.

“We are committed to working in close cooperation to integrate critical environmental considerations into our modern transportation system,” Bowen said.

Caltrans chose the second of three alternative proposals to the bridge. Project Alternative 2 calls for the construction of a 165-footwide by 200-foot-long vegetated bridge across U.S. Highway 101 with an extension over Agoura Road, a city street that runs parallel to the freeway on the south side. The first alternative had no bridge over Agoura Road.

Similar wildlife bridges have been constructed in other states and countries. The Liberty Canyon wildlife crossing would be the first of its kind in California and the largest in the western United States.

A final study states that because the project incorporates new vegetation and replanting along with proper water regulation and post-construction monitoring, it will have no adverse affect on the existing environment.

The over-crossing is planned to be built west of Liberty Canyon Road at a location endorsed by wildlife scientists and researchers, Caltrans said. It will provide a safe and sustainable animal passage and help reduce wildlife mortality. Officials say the crossing is also expected to enhance safety for motorists because large animals will no longer have a need to cross the freeway itself.

Since 1996, the National Park Service has been studying carnivores in and around the Santa Monica Mountains to determine how they survive in an increasingly fragmented and urbanized environment. During the course of the study, biologists studied the habits of more than 340 bobcats, 145 coyotes and 60 mountain lions.

A 2017 study co-written with researchers at UCLA found that a failure to increase connectivity between the Santa Monica Mountains and other wildlife habitat in Southern California would lead to the continued erosion of genetic diversity and increase the chances for mountain lion and possibly other local wildlife extinction.

Acorn staff report